Harmless softening agent for fabrics having excellent moisture absorbability

ABSTRACT

A harmless softening agent for giving excellent softness and moisture absorbability to fabrics, comprising 5 to 50 percent by weight of a natural fat and oil or the hardened product thereof and 95 to 50 percent by weight of at least one of polyvalent alcohol fatty acid esters selected from the group consisting of sugar fatty acid ester, sorbitan fatty acid ester, glycerin fatty acid ester and propylene glycol fatty acid ester, wherein the polyvalent alcohol fatty acid ester includes at least 10 percent by weight of monoester on the basis of the total weight of the fatty acid ester.

United States Patent [191 Goto et al.

11] 3,928,212 [451 Dec. 23, 1975 [75] Inventors: Sumio Goto, Uji; Kazuhiko Ishihara, Kyoto, both of Japan [73] Assignee: Dai-ichi Kogyo Seiyaku Co., Ltd.,

Japan [22] Filed: July 6, 1973 [21] Appl. No.: 377,136

[30] Foreign Application Priority Data July 12, 1972 Japan 47-70282 [52] US. Cl. 252/8.6; 427/390; 427/392; 428/272; 428/274 [51], Int. Cl. D06M 13/16 [58] Field of Search. 252/8.6, 8.9, 316; 117/1395 F; 426/201 [56] References Cited UNITED STATES PATENTS 2,067,947 l/ 1937 Platt 252/8.6 X

2,067,951 1/ 1937 Schneider 252/8.6 X 2,079,108 5/1937 Dreyfus et al. 252/8.6 X 2,113,325 4/1938 Koch 252/8.6 X

2,292,211 8/1942 Dickey 252/8.6 X 2,297,135 9/1942 252/8.6 X 2,403,305 7/1946 Rossit er et al....' 252/8.6 X 2,663,989 12/1953 Schlatter et al 252/8.9 X 3,113,369 12/1963 Barrett et al 252/8.6 X

Primary Examiner-Herbert B. Guynn Attorney, Agent, or Firm-Wenderoth, Lind & Ponack 57] ABSTRACT A harmless softening agent for giving excellent softness and moisture absorbability to fabrics, comprising 5 to 50 percent by weight of a natural fat and oil or the, hardened product thereof and 95 to 50 percent by weight of at least one of polyvalent alcohol fatty acid v esters selected from the group consisting of sugar fatty acid ester, sorbitan fatty acid ester, glycerin fatty acid ester and propylene glycol fatty acid ester, wherein the polyvalent alcohol fatty acid ester includes at least 10 percent by weight of monoester on the basis of the total weight of the fatty acid ester.

5 Claims, No Drawings iiARMLEss SOFIENING AGENT FOR FABRICS HAVING EXCELLENT MOISTURE ABSORBABILITY The present invention relates to a softening agent for giving excellent softness and moisture absorbability to fabrics. More particularly, it relates to a harmless softening agent comprising 5 to 50 percent by weight of natural fat and oil or hardened product thereof and 95 to 50 percent by weight of a polyvalent alcohol fatty acid ester type surface active agent, which can give excellent softness and moisture absorbability to fabrics of cellulose fiber (e.g. cotton, or acetate fiber) or synthetic fiber (e.g. acryl, nylon, or polyester fiber).

Hitherto, there have been known many cationic, anionic and nonionic softening agents for fabric, but not those being capable of giving both softness and moisture absorbability to fabric and further being harmless. That is, the cationic softening agent has been widely used for giving excellent softness to all kinds of fabrics of natural or synthetic fiber, but it tends to make the fabric water-repellent and therefore it can not be used for the fabric such as underwear which is desirable to be moisture absorbable. Further, the anionic or nonionic softening agent can give rather excellent softness to the fabric of cellulose fiber, but not to that of synthetic fiber.

Besides, there have been also known some methods for giving both softness and moisture absorbability to underwear or the like of synthetic fiber. For instance, it is described in Japanese Patent Publication No. 5471/1968 that the finishing of the fabric of acryl fiber is carried out by using the reaction product of the fatty acid of lanolin with ethanolamine under cooling the amount of addition thereof and thereby balancing the softness and moisture absorbability of the product. However, according to such method, the practically useful softening agent having both of excellent softness and moisture absorbability could not been produced, and therefore, there has been strongly desired for development of such excellent softening agent.

-The effectiveness of the softening agent is usually decided on the basis of its softness, but in case of underwear or the like, the moisture absorbability is one of the most important-factors. The moisture absorbability is, however, not necessarily suitable property in some kinds of fabrics which are desirable to be waterproof, and this has been become a bar to the development of the softening agent having both softness and moisture absorbability.

Moreover, the oral toxicity of the treating agent of fabrics has been recently called into question, since in clothes for baby he sometimes licks the clothes, but the conventional treating agents have rather higher toxicity as indicated by their LD value and are harmful.

Under the circumstances, it has been studied to find out more suitable softneing agent having superior properties, such as, not only excellent softness similar to that of the conventional softening agents but also excellent moisture absorbability and further being harmless to human beings. And then, it has now'been found out that an excellent softening agent can be prepared by mixing natural fat and oil or the hardened product thereof which is useful for foods with a polyvalent alcohol fatty acid ester type surface active agent which is approved as an additive for foods, and that fabrics can be given excellent softness and moisture absorbability by being treated with an aqueous or organic solution or suspension of the softening agent.

An object of the present invention is to provide a harmless softening agent for fabrics having excellent softness and moisture absorbability.

Another object of the invention is to provide a har'mless softening agent useful for all kinds of fabrics of cellulose fiber and synthetic fiber.

A further object of the invention is to provide a harmless softening agent prepared by using a material useful for foods and an additive for foods as the starting materials.

Still further object of the invention is to provide a method for fabric finishing comprising treating the fabrics with an aqueous or organic solution or suspension of the harmless softening agent.

These and other objects will be apparent from the description hereinafter.

According to the present invention, the desired softening agent can be prepared by mixing 5 to 50 percent by weight of natural fat and oil or hardened product thereof and to 50 percent by weight of at least one of polyvalent alcohol fatty acid esters, in which at least 10 percent by weight on the basis of total weight of the fatty acid ester is monoester.

As the polyvalent alcohol fatty acid esters used in the invention, there may be sugar fatty acid ester, sorbitan fatty acid ester, glycerin fatty acid ester, propylene glycol fatty acid ester and the like, which are approved as an additive for foods.

The sugar fatty acid esters may be mono-, dior tri-fatty acid ester having 12 to 18 carbon atoms. The sorbitan fatty acid esters may be mono-, dior tri-fatty acid ester having 12 to 18 carbon atoms. The glycerin fatty acid esters or the propylene glycol fatty acid esters may be monofatty acid ester having 12 to 18 carbon atoms. More particularly, the fatty acid may be a saturated fatty acid, such as lauric acid, myristic acid, palmitic acid or stearic acid, or an unsaturated fatty acid, such as oleic acid, linolic acid or linolenic acid.

Among these fatty acid esters, diand tri-fatty acid esters of sugar, and diand tri-fatty acid esters of sorbitan may be mainly used for giving softness, and other esters may be mainly used for giving moisture absorbability. When monoester is used alone as the polyvalent alcohol fatty acid ester, the softening agent shows excellent moisture absorbability but insufficient softness. When the content of dior tri-ester is increased, the softness of the agent is clearly increased.

When the content of monoester in the total weight of the fatty acid esters is less than 10 percent by weight, the softness of the agent is excellent, but the moisture absorbability is significantly lowered and the softening agent prepared therefrom loses water solubility. When various fatty acid esters are used together, sugar dior tri-fatty acid ester and sorbitan dior tri-fatty acid ester can be used similarly, i.e. both fatty acid esters can give the softening agent having similar softness and moisture absorbability. However, the monoesters are somewhat different in the softness according to the kind of polyvalent alcohol as follows:

propylene glycol glycerin 2 sorbitan 2 sugar When the content of monoester in the total weight of the fatty acid esters is 10 or more percent by weight, the softening agent can give sufficiently excellent moisture absorbability to the fabrics.

Furthermore, the softness and moisture absorbability of the softening agent are changeable according to the number of the carbon atom of the fatty acid. That is,

the carbon number being smaller, the moisture absorbability is better but the softnessis less. On the other hand, the carbon number being larger, the softness is better but the moisture absorbability is less.

When polyvalent alcohol fatty acid esters are used for the preparation of softening agent, it has, hitherto, been considered as the fatty acid esters having 16 to 18 or more carbon atoms are preferable for giving excellent softness to the softening agent and the fatty acid esters having carbon atoms of less than 16 can not give sufficient softness to the softening agent. Nevertheless, in the present invention, the fatty acid esters having smaller carbon number is used, since the fatty acid esters having smaller carbon number is more advantageous for giving moisture absorbability to the product. It has been unexpectedly found that even the fatty acid ester having 12 carbon atoms can give similar softness to the product as the fatty acid esters having 16 to 18 carbon atoms, if it includes much dior tri-ester, and further that the softness can be increased by mixing natural fat and oil to the fatty acid esters. Thus, the softness and moisture absorbability can be increased by rising the degree of the substitution of polyvalent alcohol and by mixing natural fat and oil and the hardened product thereof, even when the fatty acid ester having carbon number so lower as 12 is used.

According to the present invention, it has been found that there is a correlation between the degree of the substitution of polyvalent alcohol, i.e., the ratio of monoester, diester and triester, and the properties such as softness and moisture absorbability of the product. For instance, in case of sugar fatty acid ester, the ratio of monoester being higher, the moisture absorbability is better but the softness is less, and on the other hand, the ratio or diester and/or triester being higher, the softness is better but the moisture absorbability is less. As the results of study of the relationship between the degree of substitution of polyvalent alcohol and the length of the chain of fatty acid and the properties such as softness and moisture absorbability of the product, it

has been found that when a fatty acid ester containing at least 10 percent by weight of monoester on the basis of the total weight of the fatty acid ester is used, both softness and moisture absorbability are obtainable.

According to the present invention, it has been also found that when the softening agent is prepared by using only fatty acid esters, sufficiently excellent product can not be obtained even if it is used in best conditions, and that it is necessary to mix a natural fat and oil or the hardened product thereof to the fatty acid ester for obtaining the desired excellent softening agent. That is, when a natural fat and oil or the hardened product thereof is mixed to the fatty acid ester, the amount of the natural fat and oil or the hardened product thereof being increased, the softness is significantly increased. For instance, even when only percent by weight of the natural fat and oil or the hardened product thereof is mixed to 95 percent by weight of fatty acid ester, the softness of the product is significantly improved in comparison with the case of using the fatty acid ester alone.

For giving moisture absorbability to the fabrics, which is one of the present objects, it is preferable to use the natural fat and oil or the hardened product thereof is an amount of 50 or less percent by weight and it is necessary to use the polyvalent alcohol fatty acid ester including at least percent by weight of monoester on the basis of the total weight of the fatty acid ester. Even if 100 percent mono-fatty acid ester of sugar is used, the softening agent prepared by using 95 percent by weight of the sugar mono-fatty acid ester and 5 percent by weight of a natural fat and oil, the product shows desirable softness. Accordingly, there is no upper limitation of the contents of monoester.

The natural fat and oil or the hardened product thereof may be, for example, an animal fat and oil (e.g. beef tallow, whale oil, or hog fat), a plant fat and oil (e.g. cotton seed oil, soybean oil, coconut oil, or palm oil), and the hardened product thereof. These natural fat and oil and the hardened product thereof have been used as a material for foods and therefore, there is no anxiety in the oral toxicity.

Thus, according to the present invention, the desired harmless softening agent for fabrics having excellent softness and moisture absorbability can be obtained by mixing 5 to 50 percent by weight of natural fat and oil or the hardened product thereof and 95 to 50 percent by weight of at least one of polyvalent alcohol fatty acid ester, in which at least 10 percent by weight on the basis of total weight of the fatty acid ester is monoester. The softening agent is used in a form of a diluted aqueous or organic solution or dispersion, in which the fabric is treated by a conventional method. For instance, the fabric to be finished is steeped into a diluted aqueous or organic solution or dispersion of the softening agent at room temperature or an elevated temperature (about 30 to 50C) for a few minutes to a few hours, preferably about 10 minutes to about 1 hour, and dehydrated by a conventional method, e.g. by a centrifuge and then dried at an elevated temperature, preferably at about to 100C to give the desired fabric having excellent softness and moisture absorbability. When the softening agent is dispersible in water, it is used in a form of aqueous dispersion. But if it is hardly dispersed in water, it is dissolved in an organic solvent, such as perchloroethylene, trichloroethylene.

The present invention is illustrated by the following Examples but not limited thereto. In Examples, part and are mentioned by weight.

EXAMPLE 1 A mixture of hardened beef tallow (iodine value: 20 40; 4 parts), DK Ester F-20 (an ester of sugar with fatty acid of hardened beef tallow including about 10 percent of monoester and about percent of di-and tri-esters, made by Dai-lchi Kogyo Seiyaku Co., Ltd.; 10 parts) and Solgen 90 percent sorbitan monolaurate, made by Dai-lchi Kogyo Seiyaku Co., Ltd.; 6 parts) was heated, diluted with hot water (80 parts) and then the mixture was cooled with agitation to give the desired softening agent as a pasty substance.

By using the softening agent thus obtained, fabrics were treated as follows:

Knitted fabrics of acryl, cotton, nylon or polyester fiber and viscose rayon taffeta, which were scoured by a conventional method, were steeped into a 5 percent o.w,f. solution (o.w.f. means on the weight of fiber) of the softening agent (bath ratio: 1:20) at 40C for 15 minutes, and then the fabrics were dehydrated by a centrifuge till the contents of the solution of softening agent became 80 percent by weight on the basis of the weight of untreated fabric and dried at 80 to 100C.

The fabrics thus treated has excellent softness similar to those treated by a conventional cationic softening agent and excellent moisture absorbability as shown in Table I hereinafter.

EXAMPLE 2 In the same manner as described in Example 1, the desired softening agent (pasty substance) was prepared by using coconut oil (iodine value: 7 l l; 2 parts), DK Ester F-l60 (an ester of sugar with fatty acid of hardened beef tallowincluding about 70 percent of monoester and about 30 percent of diand tri-esters, made by Dai-lchi Kogyo Seiyaku Co., Ltd.; 7.5 parts), Solgen 50 (100 percent Sorbitan monostearate, made by Dai- Ichi Kogyo Seiyaku Co., Ltd.; 2.5 parts), propylene glycol monostearate (8 parts) and hot water (80 parts).

Knitted fabrics of acryl, cotton, nylon or polyester fiber and viscose rayon taffeta were treated by the softening agent in the same manner as described in Example 1 to give the fabrics having excellent softness and moisture absorbability. The results are shown in Table I hereinafter.

EXAMPLE 3 In the same manner as described in Example 1, the desired softening agent (pasty substance) was prepared by using cotton seed oil (iodine value: 100 120; 2 parts), hardened beef tallow (iodine value: 40; 6 parts), DK Ester F-14O (an ester of sugar with fatty acid of hardened beef tallow including about 60 percent of monoester and about 40 percent of diand tri-esters, made by Dai-Ichi Kogyo Seiyaku Co., Ltd.; 7 parts), glycerine monostearate (5 parts) and hot water (80 parts).

Knitted fabrics of acryl, cotton, nylon or polyester fiber and viscose rayon taffeta were treated by the softening agent in the same manner as described in Example 1. The results are shown in Table I hereinafter.

EXAMPLES 4 TO 11 In the same manner as described in Example 1 to 3, the desired softening agents were prepared by using the materials mentioned in Table I, and the fabrics were in Table I hereinafter.

In Examples 4 to 6 and 8 to 10, the softening agent is hardly water-soluble and therefore was issolved in an organic solvent (perchloroethylene). That is, the fabrics were steeped into a solution of the softening agent in perchloroethylene at room temperature for 15 minutes, and then dehydrated by a centrifuge till the contents of the solution of softening agent became lOO percent by weight on the basis of the weight of untreated fabric and dried at 80 to 100C. The fabrics treated by the softening agents in each Examples except Example 6 showed excellent softness and moisture absorbability. The results are shown in Table I hereafter.

EXAMPLES 12 TO 17 For the comparison with the present softening agent, various polyvalent alcohol fatty acid esters were used alone as the softening agent. The preparation of the softening agent and the treatment of the fabrics were carried out in the same manner as in the above Examples, i.e., Examples 12 and 13 were done in the same manner as in Example 1, and Examples 14 to 17 were done in the same manner as in Example 6.

The results are shown in Table I hereinafter. As made clear from the results, the products in Example 12 to 17 showed excellent moisture absorbability but inferior softness.

EXAMPLES 18 TO 19 By using the conventional softening agents prepared in the same manner as described in Example 1, the fabrics were treated in the same manner as in Example I. The results are shown in Table I hereinafter. As made clear from the results, the product in Example 18 showed excellent softness but significantly inferior moisture absorbability. On the other hand, the product in Example 19 showed excellent moisture absorbability but inferior softness.

Table I Example No. Kind Components Content of monoester in fatty acid ester Part I Hardened beef tallow (iodine value: 20 40) Ester of sugar with fatty acid of hardened beef tallow (monoester l0 Sorbitan monolaurate (monoester 100 2 Coconut oil (iodine value: 7 l l) Ester of sugar with fatty acid of hardened beef tallow (monoester Sorbitan monostearate (monoester lOO Propylene glycol monostearate (monoester I00 3 Cotton seed oil (iodine value:

Hardened beef tallow (iodine value: 20 40) Ester of sugar with fatty acid of hardened beef tallow (monoester 60 Glycerine monostearate (monoester I00 Hardened cotton seed oil (iodine value: 50 70) Sorbitan monostearate (monoester l00%) Sorbitan dioleate Hardened beef tallow (iodine value: 20 40) Glycerin monooleate (monoester l00 Hardened beef tallow (iodine value: 20 40) Ester of sugar with fatty acid of hardened beef tallow (monoester l0 Sorbitan dioleate 7 Hardened beef tallow (iodine value: 20 40) Ester of sugar with fatty acid of hardened beef tallow (monoester 40 Sorbitan monolaurate (monoester I00 Sorbitan dioleate Cotton seed oil (iodine value: I00 120) Sorbitan distearate Propyleneglycol monolaurate (monoester I00 (JIM (ANN-CW Table I-continued Example Components Content of monoester o. Kind Part In fatty acid ester 9* Cotton seed oil (iodine value: 100 120) 7.5 80

Sorbitan dioleate i 2.5 Glycerin monolaurate (monoester lOO l l0"" Hardened soybean oil (iodine value: 50 60) 8 100 Propyleneglycol monolaurate (monoester I00 2 Glycerin monooleate (monoester 100 10 ll Coconut oil (iodine value: 7 l l) 7.5 40

Ester of sugar with fatty acid of hardened beef tallow (monoester 40 l2.5 l2 Ester of sugar with fatty acid of hardened beef 2O 10 tallow (monoester l0 l3 Ester of sugar with fatty acid of hardened beef 20 60 tallow (monoester 60 1 1* Snrbitan dioleate 20 l5 Sorbitan monostearate (monoester I00 20 100 I6 Glycerin monolaurate (monoester I00 20 I00 l7 Propylene glycol monolaurate (monoester I00 20 I00 18 Cationic surgace active agent:

quaternary ammonium type (purity: 20 l9 Anionic or noionic surface active agent:

Polyvalent alcohol ester emulsion (purity: 20

Cotton Viscose rayon Acryl Nylon Polyester' Example softness Moisture softness Moisture softness Moisture softness i-loisture softness Moisture No '1 absorbabsorbabsorbabsorbabsorbabiity ability ability ability ability 1 @"O 1 -Q 2 -O 1 -O 2 O 3 2 -O 1 O 1 1 -O 1 O 3 Q 4 3 5 -O 4 3 @--O 1 a" l -O 3 8 3 7 11 1 0 2 O 2 @"Q 2 O 4 12 O-A 5 O-A 5 A 36 0-A 7 A 13 A l A- l A-X l A 1 l O-A 3 O-A 4 A O-A 3 A 7 2 A 2 A 3 A 2 A 4 A 1 A 2 A 4 A 1 A 2 n" A 2 A 2 A 4 A 2 A 5 is (o) g 300 530 5 5 19 C) l G-A 1 X 2 A 2 X [Note] *1) The softness (handng) was judged by the handling of five persons, best, O: better and A:

common, and X: bad, *2) Method for measurement of moisture absorbnbility:

Five sheets of test cloth (10 X 10 cm) were set What is claimed is:

l. A softening agent for giving excellent softness and moisture absorbability to fabrics consisting of to 50% by weight of a natural fat and oil or the hardened product thereof selected from the group consisting of beef tallow, cotton seed oil, soybean oil and coconut oil and 95 to 50% by weight of at least one of polyvalent alcohol fatty acid esters selected from the group consisting of sugar fatty acid ester, sorbitan fatty acid ester, glycerin fatty acid ester and propylene glycol fatty acid ester wherein the fatty acid moiety has 12 to 18 carbon atoms; said polyvalent alcohol fatty acid ester including at least by weight of monoester on the basis of the total weight of the fatty acid ester.

2. The softening agent according to claim 1 wherein the fatty acid is a member selected from the group consisting of lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid.

3. The softening agent according to claim 1, wherein the sugar fatty acid ester is mono-, dior tri-fatty acid ester having 12 to 18 carbon atoms in the fatty acid moiety.

4. The softening agent according to claim 1, wherein the sorbitan fatty acid ester is mono-, dior tri-fatty acid ester having 12 to 18 carbon atoms in the fatty acid moiety.

5. The softening agent according to claim I, wherein the glycerin fatty acid ester and the propylene glycol fatty acid ester are both mono-fatty acid ester having 12 to 18 carbonatoms in the fatty acid moiety. 

1. A SOFTENING AGENT FOR GIVING EXCELLENT SOFTNESS AND MOSITURE ABSORBABILITY TO FABRIC CONSISTING OF 5 TO 50% BY WEIGHT OF A NATURAL FAT AND OIL OR THE HARDENED PRODUCT THEREOF SELEATED FROM THE GROUP CONSISTING OF BEEF TALLOW, COTTON SEED OIL, SOYBEAN OIL AND COCONUT OIL AND 95 TO 50% BY WEIGHT OF AT LEAST ONE OF POLYVALENT ALCOHOL FATTY ACID ESTERS SELECTED FROM THE GROUP CONSISTING OF SUGAR FATTY ACID ESTER, SORBITAN FATTY ACID ESTER, GLYCERIN FATTY ACID ESTER AND PROPYLENE GLYCOL FATTY ACID ESTER WHEREIN THE FATTY ACID MOIETY HAS 12 TO 18 CARBON ATOMS, SAID POLYVALENT ALCOHOL FATTY ACID ESTER INCLUD ING AT LEAST 10% BY WEIGHT OF MONOESTER ON THE BASIS OF THE TOTAL WEIGHT OF THE FATTY ACID ESTER.
 2. The softening agent according to claim 1 wherein the fatty acid is a member selected from the group consisting of lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid.
 3. The softening agent according to claim 1, wherein the sugar fatty acid ester is mono-, di- or tri-fatty acid ester having 12 to 18 carbon atoms in the fatty acid moiety.
 4. The softening agent according to claim 1, wherein the sorbitan fatty acid ester is mono-, di- or tri-fatty acid ester having 12 to 18 carbon atoms in the fatty acid moiety.
 5. The softening agent according to claim 1, wherein the glycerin fatty acid ester and the propylene glycol fatty acid ester are both mono-fatty acid ester having 12 to 18 carbon atoms in the fatty acid moiety. 